KR930001712B1 - Varnish impregnation method and apparatus - Google Patents

Abstract

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Description

Varnish Impregnation Method and Apparatus

1 is a cross-sectional view showing a first embodiment of the varnish impregnation apparatus according to the present invention.

2A and 2B are explanatory diagrams showing the penetrating action of the low-viscosity liquid, respectively.

3 is a temperature and vapor pressure diagram of methyl ethyl ketone as a low viscosity liquid.

4 is a sectional view showing a second embodiment of the varnish impregnation apparatus according to the present invention.

5 is a cross-sectional view showing a third embodiment of the varnish impregnation apparatus according to the present invention.

6 is a sectional view of a main portion of the apparatus, showing a modification thereof.

7 is a sectional view of a device showing a modification thereof.

8 is a sectional view showing a fourth embodiment of the varnish impregnation apparatus according to the present invention.

9 to 11 are cross-sectional views of devices each showing a modification thereof.

12 is a longitudinal sectional side view showing a fifth embodiment of the varnish impregnation apparatus according to the present invention.

13 and 14 are cross-sectional views of the apparatus each showing a modification thereof.

* Explanation of symbols for main parts of the drawings

DESCRIPTION OF SYMBOLS 1 Base material 2 Low viscosity liquid storage tank

2 ': low viscosity liquid storage area 3: varnish storage tank

3 ': varnish storage area 4: thermosiphon chamber

4 ': thermal siphon zone 5: substrate heating mechanism

5a: heating roll 6: cooling mechanism

6a: cooling furnace 6b: first cooling coil

6c: second cooling coil 7: guide mechanism

8: condensate recovery mechanism 9: varnish impregnation amount adjustment mechanism

12: low viscous saturated liquid 12S: low viscous liquid vapor

13 varnish 14: additional organ

15 exhaust pump 16 pressure control device

22: inert gas supply pipe 23: inert gas exhaust pipe

31: condensation prevention mechanism 32: base material passage

36: steam jet nozzle 37: steam leak prevention cooler

Th: Substrate heating temperature Tw: Varnish temperature

Ts: low viscosity liquid temperature Tc: cooling coil temperature

Pc: Vapor pressure of cooling coil part Ph: Vapor pressure of substrate heating part

Ps: low viscosity liquid vapor pressure Pw: varnish liquid vapor pressure

The present invention relates to a method and an apparatus for impregnating a varnish on a sheet-like substrate made of fibrous materials such as paper and fabrics used in the production of laminated plates such as electrical insulating plates and decorative plates. In general, when the varnish is impregnated with a sheet-shaped substrate made of a fiber material, it is important that the varnish is impregnated to the inside of the fiber of the substrate so that the varnish amount distribution of each part is uniform without staining, and the bubbles remaining in the substrate are As little as possible is required.

In the conventional impregnation method, in general, after preliminary impregnation of the base material into the usual varnish for pre-impregnation, it is customary to guide the varnish through a mill mill roll to impregnate the varnish.

By the way, in this impregnation method, it is difficult to uniformly and sufficiently impregnate the varnish to the inside of the base material, it takes a long time to impregnate the varnish, and it is difficult to sufficiently reduce the bubbles remaining in the base material.

This problem is particularly noticeable when varnishes of high viscosity are used. Thus, in recent years, a pre-impregnation tank containing a thin varnish (hereinafter referred to as "preliminary impregnation liquid") containing a large amount of a solvent or a solvent in place of the above-mentioned conventional varnish for pre-impregnation and a main impregnation tank containing a conventional varnish, The substrate is passed through the preliminary impregnation tank and this impregnation tank in order by a guide roller.

By this impregnation method, while the substrate is passed through the pre-impregnation liquid, the air in the substrate is replaced by the pre-impregnation liquid, so that the substrate is brought into the varnish while evaporating the pre-impregnation liquid impregnated with the substrate, the varnish is In addition to being able to be impregnated with high efficiency, bubbles can be reduced.

However, in the transition step from the pre-impregnation liquid to the varnish, the substrate comes into contact with the air and is subjected to the compression action by the guide roll between the impregnation tanks, so that the air removal in the substrate is not sufficiently achieved, and the varnish impregnation and the visible It is difficult to expect too much of a voidless effect.

That is, when the substrate reaches the roll described above, the contact surface pressure acts on the fibers constituting the substrate to open the fiber bundle, and the liquid phase of the pre-impregnation liquid held by the capillary force of the fiber bundle is destroyed. Then, the compression of the fiber bundle is released at the time when it passes through the guide roll, but the fiber bundle opened by this decompression action is reformed. As described above, since the impregnation liquid phase breakdown in the fiber bundle and the remodeling of the opened fiber bundle are performed in air, there is a fear that air is re-intruded into the substrate during the transition from the pre-impregnation liquid to the varnish.

An object of the present invention is to firstly impregnate the varnish in a short time in a uniform and sufficient manner, and to further eliminate all bubbles in the base material, thereby significantly improving the quality of the final product such as an electrical insulation plate and a decorative plate. The present invention provides an impregnation method and apparatus for obtaining a frame fragmentation.

Secondly, it is to provide a varnish impregnation method and apparatus capable of drastically miniaturizing and simplifying the structure of a device without requiring a tumble mill or the like.

Third, the present invention provides a varnish-impregnation method and apparatus in which the amount of low-viscosity liquid used in the base material is extremely small, and in the drying step after the external varnish impregnation, the amount of exhaust gas can be greatly reduced by drying.

Fourth, to provide a varnish impregnation method and apparatus that can effectively prevent the loss of branch liquid and dilution of the varnish, and can promote the varnish impregnation action.

Fifth, the present invention provides a varnish impregnation method and apparatus capable of maintaining a good varnish impregnation and capable of maintaining a constant vapor pressure in a thermosiphon region at all times despite changes and variations in varnish impregnation conditions such as substrate speed.

Sixth, it does not require a high-precision pressure control device or the like, does not complicate and enlarge the device structure, and more precisely and accurately perform steam pressure control in the thermosiphon region than in the case of the pressure control device. It is to provide a method and apparatus that can be.

Seventh, even when the thermosiphon interior becomes a major or negative pressure state during operation stoppage, such occurrences are prevented, and low viscosity liquids and varnishes are sucked into the thermosiphon chamber. To provide a method and apparatus that is not. This object is achieved by a varnish impregnation method and apparatus as follows.

In the method of the present invention, a thermosiphon region is provided between the low-viscosity storage region containing a low-viscosity liquid such as a solvent and the varnish storage region containing a varnish, and the thermosiphon region communicating with the liquid is sealed at the liquid level. The sheet-like substrate made of ash is passed through the low-viscosity storage region, the thermosiphon region, and the varnish storage region in order, and the substrate is heated in the thermosiphon region to evaporate the low-viscosity liquid impregnated therein.

In the portion of the substrate passing region from the substrate heating portion in the thermosiphon region to the varnish storage region, it is preferable to heat or keep the substrate above the condensation temperature of the low-viscosity vapor. The low-viscosity vapor generated in the thermosiphon region is preferably condensed and recovered.

The thermosiphon region is connected to the low-viscosity liquid storage region in a liquid sealed state at the liquid level, and the low-viscosity liquid in the communicating portion is heated and evaporated to control the amount of evaporation according to the variation of the liquid sealing surface in the communicating portion. It is good.

In the thermosiphon region, it is preferable to allow the low-viscosity vapor generated in the region to flow from the substrate outlet side toward the substrate inlet direction. It is preferable that only the communicating portion between the thermosiphon region and the varnish storage region be heated and kept at a temperature above the boiling point of the low-viscosity liquid. An apparatus for carrying out such a method includes a low-island liquid storage tank in which low-viscosity liquids such as solvents are stored, and a liquid level of the base inlet portion and the varnish storage tank which are opened at the lower or upper surface of the varnish storage tank and the viscous liquid storage tank in which the varnish is stored. A thermosiphon chamber having a base outlet opening in the lower portion, a guide mechanism for guiding the sheet-shaped substrate made of fibrous material to pass through the low-viscosity storage tank, the thermosiphon chamber, and the varnish storage tank, and the substrate in the thermosiphon interior. And a substrate heating mechanism for evaporating the impregnated branch liquid.

In this apparatus, a cooling mechanism for condensing the low viscosity liquid vapor in the thermosiphon chamber and a condensate recovery mechanism for recovering the low viscosity liquid condensed by the cooling mechanism may be provided. In the substrate passing area portion from the substrate heating mechanism to the opening end of the substrate outlet, a condensation preventing mechanism for heating or keeping the substrate above the condensation temperature of the low-viscosity vapor is provided.

When the substrate inlet is opened under the liquid level of the low-viscosity liquid storage tank, the low-viscous liquid heating surface extending in the vertical direction is disposed in the low-viscosity liquid in the substrate inlet, and the heating evaporation amount of the low-viscosity liquid changes according to the liquid level variation of the low-viscosity liquid. And a low viscosity liquid heating mechanism configured to.

The base outlet is provided with a low viscosity liquid storage part and a low viscosity liquid heater, and heats and evaporates the low viscosity liquid in the viscous liquid storage part and flows the low viscosity liquid vapor generated in the thermosiphon room from the substrate exit part toward the substrate inlet part. A steam flow mechanism is provided. In this case, it is preferable to keep the low viscosity liquid storage tank and the low viscosity liquid storage part in communication.

A vapor flow mechanism is provided at the base inlet and provided with a low viscosity liquid recovery part communicating with the low viscosity liquid storage part, and a cooler disposed in the low viscosity liquid recovery part. The circumferential wall of the thermosiphon seal has a jacket structure so as to supply and flow a heating medium into the jacket, and to heat the boundary portion with the varnish liquid surface in the base exit portion to a boiling point of the low viscosity liquid above the boiling point. The cross-sectional area of the substrate passage at the substrate outlet is set so as to be the minimum in a range that allows passage of the substrate. It is preferable to provide a varnish impregnation amount adjusting mechanism for adjusting the varnish amount contained in the substrate having passed through the varnish storage tank and to provide a vapor ejection nozzle for supplying a low viscosity liquid vapor into the thermosiphon interior.

The upper surface of the low-viscosity liquid storage tank is closed with a lid attached to the substrate inlet, and a vapor leak preventing cooler is provided at the inlet of the substrate formed by the cap.

1 shows a first embodiment of the present invention. The varnish impregnation apparatus of this experimental example is a varnish storage tank (3) having both a low-viscosity liquid storage tank having an open shape and a top-side varnish storage tank (3) in which a predetermined amount of a low-viscosity liquid (12) such as a solvent is stored, and a storage tank (2), both storage tanks. A thermosiphon chamber (4) disposed between (2) and (3), a substrate heating mechanism (5) for heating the substrate (1) in the thermosiphon chamber (4), and a cooling mechanism for condensing the low-viscosity vapor ( 6), a guide mechanism 7 for guiding the substrate 1 along a predetermined path, a condensate recovery mechanism 8 for recovering the condensed low viscosity liquid 12, a varnish impregnation amount adjustment mechanism 9, and the like. Equipped.

The substrate is in the form of a sheet made of a fibrous material, and synthetic, natural organic, woven and nonwoven fabrics made of inorganic fibers are used. As the low-viscosity liquid 12, one having a property of sufficiently wetting with respect to the substrate 1 is used. Specifically, a viscosity solvent having a viscosity lower than 100CP or the like of the varnish 13 is used, but it is preferable to use a solvent having the same content as the solvent blended with the varnish to be impregnated, even if it is incorporated into the varnish 13. Because there is no problem. In addition, the low viscosity liquid 12 is maintained at predetermined temperature Ts by the temperature control apparatus which is not shown in figure.

As the varnish 13, a thermosetting resin varnish is generally used, but varnishes such as gauze, thermoplastic resins, natural resins, liquid synthetic resins, solvent-free natural resins, and the like are also used. The varnish 13 is maintained at a predetermined temperature Tw higher than the low viscosity liquid temperature Ts by a temperature controller not shown in the figure.

The thermosiphon chamber 4 is arranged in the upper part between both the storage tanks 2 and 3, and the station U which vertically provided the cylindrical base material inlet part 4a and the base material outlet part 4b in the bottom wall part is installed vertically. The siphon tube shape is formed.

The substrate inlet portion 4a and the substrate outlet portion 4b are opened under the liquid surfaces 12 'and 13' of the low viscosity liquid storage region 2 'and varnish storage region 3', respectively, and are thermosiphoned. The inside of the chamber 4 is formed with the thermosiphon region 4 'sealed by the liquid rod.

The substrate inlet portion 4a is designed to increase its cross-sectional area and to increase the area of the condensation portion of the low-viscosity saturated steam. The substrate outlet portion 4b has a small cross-sectional area and evaporation portion of the low-viscosity saturated steam. It is designed to be narrow in area.

The main wall of the thermosiphon chamber 4 including the substrate inlet portion 4a and the substrate outlet portion 4b is composed of a heat insulating wall, so that the low-viscosity vapor is cooled by the external air and the inside of the thermosiphon chamber 4 It is designed to prevent condensation on the wall. In addition, an additional pipe 14 is connected to the thermosiphon chamber 4.

An exhaust pump 15 and a pressure control valve 16 are provided in the weight pipe 14 to remove the air in the thermosiphon region 4 'and to control the region 4' pressure. .

In addition, the weight pipe 14 is guided to the air separator 17 to separate and recover the low-viscosity liquid vapor 12s contained in the air discharged from the weight pipe 14 from the saturated liquid 12. The low viscosity liquid 12 separated by the air separator 17 is recovered to the low viscosity liquid storage tank 2 via the recovery pipe 18. The base material heating mechanism 5 is rotatably provided so that the heating roll 5a of the thermosiphon chamber 4 can follow the circulation of the base material 1.

This heating roll 5a heats the base material 1 at the boiling point of the low-viscosity liquid 12 or near its boiling point in the thermosiphon region 4 ', and evaporates the low-viscosity liquid 12 to be impregnated therein. . The heating roll 5a may be rotated in the passing direction of the machine 1. In this case, it goes without saying that the roll circumferential speed must match the traveling speed of the substrate 1.

Although the substrate heating temperature Th (> Tw) by the heating roll 54a is controlled by the temperature control apparatus not shown in the figure, the evaporation capability is impregnated in the substrate 1 and carried in into the thermosiphon chamber 4. It is sufficient to evaporate the maximum amount of low-viscosity liquid. The cooling mechanism 6 is provided with the cooling coil 6a arrange | positioned at the upper end part of the base-material exit part 4b in the thermosiphon chamber 4. The cooling coil 6a condenses and liquefies the low-viscosity vapor 12s generated in the thermosiphon region 4 'at the substrate outlet portion 4b to effectively perform the thermosiphon phenomenon and to provide a low-viscosity liquid vapor ( 12s) avoids condensation in the varnish storage region 3 'as much as possible. The cooling coil temperature Tc is kept lower than the low viscosity liquid temperature Ts. The travel guide mechanism 7 includes a guide roll 7a disposed above the low viscosity liquid storage tank 2 and in each of the storage tanks 2 and 3. , (7b)... The substrate 1 passes from the substrate supply source 1 'through the low viscosity liquid storage region 2', reaches the substrate siphon region 4a to the thermosiphon region 4 ', and the heating roll 5 And through the cooling coil 6a to reach the varnish storage tank 3 from the base outlet 4b, and pass through the varnish impregnation amount adjusting mechanism 9 through the varnish storage region 3 '.

Guide rollers 7a disposed in the respective storage areas 2 ', 3'. , The expander type which can give new power to the at least one base material 1 of 7b in the width direction, and the low viscosity liquid storage area | region perpendicular to the advancing direction of the base material 1 ( Substitution of air and the low-viscosity liquid in 2 ') and varnish impregnation in the varnish storage region 3' are promoted, respectively.

The condensate recovery mechanism 8 is arranged at a lower position of the bottom wall portion of the thermosiphon chamber 4 immediately below the cooling coil 6a to form a condensate flow 8a, and is connected to the substrate from the condensate 8a. The lower surface 8b is formed to be inclined downward from the inlet portion 4a.

The varnish impregnation amount adjusting mechanism 9 is formed by disposing a squeeze roll or a squeeze bar on the varnish storage tank 3, and squeezes the base material 1 that has passed the varnish storage tank 3 to the varnish. Adjust the impregnation amount.

With the varnish impregnation device configured as described above, the method of the present invention is carried out as follows. First, the base material 1 reaches the low viscosity liquid storage tank 2 from the base material supply source 1 'and is immersed in the low viscosity liquid 12, and the air in the base material 1 is replaced with the low viscosity liquid 12. As shown in FIG. That is, when the base material 1 reaches the liquid level of the low viscosity liquid 12, the low viscosity liquid 12 penetrates into the fiber bundle 1a constituting the base material 1 by capillary shape, and at the same time, The air in the fiber bundle 1a is extruded. This penetrating action is stopped at any stage because of the penetration resistance in the fiber bundle 1a.

The stoppage of the penetrating action is the liquid surface 12 'when the traveling speed of the substrate 1, and eventually the penetration speed V ₁ of the fiber bundle 1a into the low-viscosity liquid 12 is greater than the penetration speed V ₂ . It is generated above (see also part 2a), and when V ₁ <V ₂ , it occurs below the liquid level 12 '(see also part 2b).

Accordingly, while the substrate 1 passes through the low-viscosity storage region 2 ', it is acted upon by the expander-type guide roll 7a and interacts with each other so that all the air in the fiber bundle 1a is low-viscosity 12 ) And are excluded.

Then, the substrate 1 impregnated with the low-viscosity liquid 12 reaches the inside of the thermosiphon chamber 4 from the substrate inlet portion 4a opened under the liquid level of the low-viscosity liquid storage region 2 ', and the heating roll 5a. By heating, the low viscosity 12 impregnated in the substrate 1 is evaporated off.

At this time, the substrate 1 serves as a wick as a thermosiphon by continuously supplying the low-viscosity liquid 12 to the substrate heating unit 5 as the moving speed thereof. On the other hand, in the thermosiphon chamber 4, air is preliminarily removed by the exhaust pump 15, and the air is filled with saturated steam of the low-viscosity liquid.

In addition, since the substrate heating temperature (Th)> varnish temperature (Tw)> low viscosity liquid temperature (Ts)> cooling coil temperature (Tc), the vapor pressure of each part of the low viscosity liquid 12 in the thermosiphon region 4 ' Substrate Heating Part Vapor Pressure (Ph)> Varnish Liquid Vapor Pressure (Pw)> Low Viscosity Liquid Vapor Pressure (Ps)> Cooling Coil Part Vapor Pressure (Pc) The low-viscosity vapor (12s) is moved at the speed of sound by this pressure gradient. Most of them are recovered from the base material heating part 5a to the low viscosity liquid storage tank 2 and do not invade the varnish storage tank 3.

That is, as shown in FIG. 1, the low-viscosity vapor 12s generated in the substrate heating section 5a is flowed back into the low-viscosity storage tank via the substrate inlet section 4a from the thermosylyzer chamber 4 or the cooling coil. It liquefies by (6a) and flows back into the low viscosity liquid storage tank (2) via the oil surface (8b) in the condensate (8a).

Therefore, the substrate 1 heated in the thermosiphon chamber 4 contains the low viscosity liquid 12 and the saturated steam 12s, and the varnish storage tank 3 from the substrate outlet portion 4b in the state of not containing air. Is reached and immersed into the varnish 13. At this time, the substrate 1 is brought into the varnish storage region 3 'in a state of not contacting the air in the liquid sealing portion 13a of the substrate outlet portion 4b, and the varnish storage region (in the thermosiphon region 4') In step 3 '), air does not enter the base material 1.

When the low-viscosity saturated steam 12s contained in the base material 1 enters the varnish storage region 3 ', it becomes a small amount of the low-viscosity liquid saturated liquid and diffuses into the varnish 13. Accordingly, the varnish 13 is uniformly and sufficiently impregnated with the substrate 1 while the substrate 1 passes through the varnish storage region 3 '.

At this time, as described above, the soy flour of the low-viscosity liquid vapor 12s generated in the thermosiphon chamber 4 is recovered to the low-viscosity liquid storage tank 2, and the varnish storage tank 3 is directly by the substrate 1. Since the viscosity of the low viscous liquid saturated steam 12s carried in is small, the varnish viscosity in the varnish storage tank 3 does not fall.

In addition, when the base material 1 passes through the expander-type guide rolls 7a and 7b, new power is applied in the width direction, and this new power is released after the passage of the roll, so that the low viscosity liquid 12 and the varnish 13 In the width direction, the fiber speed is expanded and reprocessed in the width direction, so that the substitution of air and low viscosity liquid in the width direction and the impregnation of the varnish are also improved.

As a result, the varnish 13 is sufficiently impregnated inside the fiber bundle of the base material 1. As the base material 1, a composition having the glass cloth # 7628 for electromagnetic materials as the varnish 13 shown in the table below, and methyl ethyl ketone, which is a compounding solvent of the varnish 13, were used as the low-viscosity liquid 12, respectively. The above-mentioned apparatus was operated under a temperature condition of Th = 150 ° C, Tw = 30 ° C, Ts = 30 ° C, and Tc = 10 ° C, and the amount of low-viscosity liquid conveyed to the varnish storage tank 3 was extremely small (by volume%). 10% and 0.0128% by weight), all the bubbles in the substrate 1 are removed without causing troubles such as the varnish viscosity of the varnish storage tank 3 being lowered, and the varnish 13 is applied to the substrate 1. Was confirmed to be uniform and sufficiently impregnated.

In addition, the temperature and vapor pressure diagram of methyl ethyl ketone used as the low viscosity liquid 12 are as shown in FIG.

[Varnish composition]

4 shows a second embodiment of the present invention.

The varnish impregnation apparatus of this embodiment includes a branch liquid storage tank 2, a varnish storage tank 3, a thermosiphon chamber 4, a base material heating mechanism 5, a cooling mechanism 6, a guide mechanism 7, and a condensate recovery mechanism. (8), varnish impregnation amount adjusting mechanism 9, low viscosity liquid heating mechanism 21, and the like are distinguished.

Obava boards 2a, 3b and Ovafu oil tanks 2b, 3b are provided on the side walls of each of the storage tanks 2, 3, and the liquid level in each storage tank 2, 3 is provided. It is designed to keep the height constant. The liquid in the oil tanks 2b and 3b is returned to the storage tanks 2 and 3 by a companion device not shown in the drawing. The thermosiphon chamber 4 is connected to a weight pipe 14, an inert gas supply pipe 22, and an exhaust pipe 23.

The cooling mechanism 6 arrange | positions the upper part of the 1st cooling coil 6b arrange | positioned above the low-viscosity liquid 12a in the base material inlet part 4a, and the varnish storage 13a in the base material outlet part 4b. And a second cooling coil 6c. However, the cooling capacity by the first cooling coil 6b, that is, the condensation capacity, is sufficient to condense all the viscous liquid evaporated by the heating roll 5a. That is, it is more than the evaporation capacity of the heating roll 5a.

In addition, the condensation capacity of the second cooling coil 6c is lower than that of the first cooling coil 6b, and is about 10 to 20%. The cooling coils 6b and 6c are insulated from each other by the circumferential wall of the thermosiphon chamber 4, and the defects caused by the cooling action of the cooling coils 6b and 6c are caused by the circumferential wall. For example, it aims to prevent the defect that low viscosity liquid vapor condenses on the inner surface of a peripheral wall.

The low-viscosity liquid heating mechanism 21 heats and evaporates the low-viscosity liquid of the low-viscosity liquid stream 12a. For example, the low-viscosity liquid heating surface 21a is formed of a heat transfer coil for flowing a heating medium therein and extends in the vertical direction. It is made to arrange | position to the low viscosity liquids 12a.

The heating capacity of the low-viscosity liquid heating mechanism 21, that is, the low-viscosity liquid evaporation capacity is at least sufficient to ensure a substantial evaporation amount for the condensation force (total amount) by both cooling coils 6b and 6c. . Moreover, between the low viscosity liquid heating surface 21a and the circumferential wall of the thermosiphon chamber 4 is insulated, and it is extremely strong that heat in the low viscosity liquid 12a is transferred to the surrounding low viscosity liquid 12. We are trying to prevent it.

The condensate recovery mechanism 8 is provided at the position just below the second cooling coil 6c to connect the condensate flow 8a to the inner circumference of the base outlet 4b, and to form the low viscosity liquid storage tank from the condensate 8a. (2) (More specifically, the low viscosity liquid condensed by the 2nd cooling coil 6c is guide | induced by inducing | recovering pipe | tube 8c to the low viscosity liquid 12a of the base material inlet part 4a. The low viscosity liquid condensed by the first cooling coil 6b is recovered to the low viscosity liquid 12a using the base inlet 4a as it is. The constitution flow 8b of the condensate 8a described above is constituted by a heat insulation wall that insulates the substrate 1 from the second cooling coil 6c, and the substrate 1 is attached to the cooling coil 6c. It is intended to prevent the low-viscosity increase from condensation adhered to the base material 1 by spinning by cooling.

The configuration other than such a configuration is the same as that of the first embodiment, and thus the details thereof are omitted. In order to start the apparatus, the inside of the thermosiphon chamber 4 is filled with the saturated vapor of the low-viscosity liquid and the steam pressure is maintained in a constant range as follows. First, an inert gas is supplied from the supply pipe 22 to the thermosiphon chamber 4, and air in the thermosiphon chamber 4 is removed through the exhaust pipe 23. At this time, the inside of the thermosiphon chamber 4 is maintained at atmospheric pressure.

Therefore, the liquid level 12'a, 13'a of the low viscosity liquid 12a and the varnish 13a are the same height as the liquid level 12 ', 13' of the storage tank 2, (3). (See Figure 4, solid line).

Next, each of the heating mechanisms 5 and 21 is operated to generate low viscosity liquid vapor mainly in the low viscosity liquid heating mechanism 21 in the thermosiphon chamber 4. At the same time, only the second cooling coil 6c having a low cooling capacity is operated to condense the low-viscosity vapor. Therefore, since the 1st cooling coil 6b of a high cooling capacity is not operated, the amount of evaporation by both heating mechanisms 5 and 21 exceeds the amount of condensation by the 2nd cooling coil 6c, The vapor pressure in the thermosiphon chamber 4 rises.

At this time, by forcibly opening the bleed valve 16 of the plunger 14, excess steam in the thermosiphon chamber 4 is removed from the plunger 14 by the low-viscosity liquid storage tank 2, and the thermosiphon chamber 4 The interior is maintained at atmospheric pressure. On the other hand, each sealing liquid surface 12'a, 13'a is not fluctuate | varied and is maintained at the solid line position of FIG.

In addition, the low-viscosity liquid condensed by the second cooling coil 6c is collected in the condensate liquid stream 8a and recovered from the recovery pipe 8c to the low-viscosity liquid stream 12a. This prevents condensation of the low-viscosity vapor into the varnish storage region 3 '.

By repeating such an operation, the inert gas in the thermosiphon chamber 4 is extracted, and the chamber 4 is filled with a low viscous liquid vapor. When the thermosiphon chamber 4 is filled with low-viscosity vapor, the bleed valve 16 is forcibly closed to raise the pressure in the thermosipine chamber 4. At this time, as the pressure rises in the thermosiphon chamber 4, the sealing liquid surfaces 12'a and 13'a are lowered (refer to FIG. 4). As the liquid surface 12'a of the low viscosity liquid 12a falls, the heating surface 21a and the low viscosity liquid are immersed in the low viscosity liquid 12a in the immersion depth of the heating surface 21a. As the contact area decreases, the amount of evaporated by the low-viscosity liquid heating mechanism 21 decreases, thereby achieving equilibrium with the amount of condensation of the second cooling coil 6c.

Subsequently, when the first cooling coil 6b is operated, the amount of condensation of the low-viscosity liquid vapor increases, and the pressure in the thermosiphon chamber 4 decreases, so that each sealing liquid surface 12'a, 13'a is To rise.

As the liquid surface 12'a of the low-viscosity liquid 12a rises, the contact area between the low-viscous liquid heating surface 21a and the low-viscous liquid increases, and the amount of evaporation by the low-viscous liquid heating mechanism 21 increases, thereby cooling. Equilibrium with the amount of condensation of the coils 6b and 6c and the vapor pressure in the thermosiphon chamber 4 are maintained within a certain range.

After making the substrate 1 run in this state, the varnish impregnation of the substrate 1 is performed as in the first embodiment. However, the vapor pressure in the thermosiphon chamber 4 is such that the amount of evaporation of the low viscosity liquid 12 by the base material heating mechanism 5 and the low viscosity liquid heating mechanism 21 and the amount of condensation by the cooling mechanism 6 are in an equilibrium state. However, if the varnish impregnation conditions such as the traveling speed of the substrate are changed and varied, the balance between the above-mentioned evaporation amount and the condensation amount is broken, and the steam pressure in the thermosiphon chamber 4 is changed, thereby causing the above-described action. There is a possibility that this may not be performed satisfactorily.

However, if the vapor pressure in the thermosiphon chamber 4 fluctuates, the liquid level 12'a of the low-viscosity liquid 12a and the liquid level 13'a of the varnish 13a are also fluctuated accordingly. Accordingly, the amount of evaporated by the low viscosity liquid heating mechanism 21 is automatically controlled.

That is, when the vapor pressure falls and the liquid surface 12'a of the low viscosity liquid 12a rises, the connection area between the low viscosity liquid 12 and the low viscosity liquid heating surface 21a in the low viscosity liquid 12a is increased. This increases (for example, it becomes the state shown by the solid line in FIG. 4).

As a result, the amount of evaporation by the low-viscosity liquid heating mechanism 21 is increased only by an amount corresponding to the amount of decrease in the evaporation pressure, and the steam pressure in the thermosiphon chamber 4 is prevented from being lowered. On the contrary, when the vapor pressure is increased, the liquid surface 12'a of the low viscosity liquid stream 12a is lowered, and the contact area between the low viscosity liquid 12 and the low viscosity liquid heating surface 21a is reduced (for example, It is in the state shown by the broken line in FIG. Therefore, the amount of evaporation by the low viscosity liquid heating mechanism 21 decreases, and the increase of steam pressure is prevented.

In this way, the steam pressure in the thermosiphon chamber 4 is self-controlled without providing a pressure control device or the like, and is always maintained in a constant range. In the case where the substrate running is stopped due to the stop of operation, or when the substrate running speed is changed or fluctuated, the condensation amount by the cooling mechanism 6 greatly exceeds the evaporation amount due to the substrate heating. 4) Although there is a possibility that the inside becomes a vacuum or a negative pressure and the low viscosity liquid 12 and the varnish 13 are attracted to the thermosiphon chamber 4 from the base inlet 4a and the base outlet 4b, Even in this case, such defects do not occur at all.

5 shows a third embodiment of the present invention.

The varnish impregnation device of this embodiment includes a low viscosity liquid storage tank 2, a varnish storage tank 3, a thermosiphon chamber 4, a base material heating mechanism 5, a cooling mechanism 6, a guide mechanism 7, and a condensate recovery mechanism. (8), varnish impregnation amount adjusting mechanism 9, low-viscosity liquid heating mechanism 21, condensation preventing mechanism 31, and the like.

The circumferential wall 4c of the thermosiphon chamber 4 is constituted of a jacket structure except for the bottom wall portion that planets the oil lower surface 8b, and the low-viscosity liquid 12 is supplied by supplying and flowing a suitable heating medium in the jacket. Heating and warming above the boiling point, and the pressure in the thermosiphon chamber 4 to reach the saturated vapor pressure of the low-viscosity liquid 12 at the time of starting the device, that is, to start the rapid operation, ) Is designed to prevent condensation on the inner surface of the circumferential wall 4c.

Of course, the outer wall and the bottom wall of the jacket in the circumferential wall 4c are made of a heat insulating material. The anti-condensation mechanism 31 is provided by providing a substrate passage 32 surrounding the substrate passage region portion 32 'from the position near the heating roll 5a to the varnishes 13a. The substrate passing passage 32 constitutes the substrate exit portion 4b, the lower end portion of which is described above, and the peripheral wall is constituted by the heating walls 32a and 32b of the jacket structure.

The heating walls 32a and 32b provide a low viscosity liquid to the substrate 1 in the substrate passage 32, that is, the substrate passage region portion 32 'by supplying a suitable heating medium therein. It heats and heats more than the condensation temperature of steam 21s.

In particular, a higher temperature heating medium is supplied to the lower heating wall 32b surrounding the varnishes 13a, and the liquid surface 13'a portion of the varnishes 13a is brought to a boiling point of the low-viscosity liquid 12. It is designed to heat above. Of course, it is also possible to supply and flow the same high temperature medium to the upper heating wall 32a.

In this case, both heating walls 32a and 32b can be comprised by a series of jacket structure. In addition, the outer wall of the jacket in each heating wall 32a, 32b is comprised by the heat insulating material, and is considered so that the heat in the base material passage 32 may not be conducted to the surroundings. As a result, the cooling action by the cooling mechanism 6 is reduced or the varnish 13 around the varnish 13a is not considered to be heated.

In addition, it is preferable that the upper end of the substrate passing passage 32 be as close as possible to the heating roll 5a. The configuration other than such a configuration is the same as that of the second embodiment, and thus the details thereof are omitted. However, the condensate recovery mechanism 8 is configured similarly to the first embodiment. In this embodiment, the base material 1 which has passed through the heating roll 5a continues to enter the base material passage 32, and passes through this to be brought into the varnish 13a.

At this time, in the substrate passage 32, the varnish is heated and maintained at the condensation temperature of the low-viscosity vapor 12s by the heating action by the heating walls 32a and 32b. The low-viscosity liquid vapor 12a in the substrate passage area portion 32 'reaching (13a) is condensed by radiation cooling by the cooling mechanism 6 to adhere to the substrate surface or invade varnish 13a. There is no

By the way, since the varnish temperature is generally lower than the saturated vapor temperature of the low viscosity liquid, when the base material 1 enters the varnish 13, the low viscosity liquid vapor 12s contained therein is condensed. However, since the liquid surface 13'a portion of the varnishes 13a is heated above the boiling point of the low-viscosity liquid 12 by the lower heating wall 32b, the varnish 13a can enter the varnish 13a as described above. The condensate that occurs is re-evaporated and hardly penetrates into the varnish 13. In this fact, there is little fear of invading into the varnish 13 of the low-viscosity liquid 12 as the base 1 enters, and there is no fear that the varnish 13 will be diluted.

In the above varnish impregnation apparatus, the heating walls 32a and 32b described above are constituted by simple heat insulating walls, and the substrate 1 passing through the substrate passage pipe 11 is transferred to the cooling mechanism 6. It is also possible to block from the cooling action by the heat insulator and to thermally insulate the substrate 1 and its surrounding temperature above the condensation temperature of the low-viscosity liquid 12 during the heating roll 5a to the varnishes 13a.

In addition, a portion of the heating wall 32a (or a heat insulating wall portion instead of this) positioned on the oil surface 8b may not necessarily have a cylindrical shape completely surrounding the base material 1, and varnishes 13a The heating device of the part is also not limited to the heating wall 32b of a jacket structure, and is arbitrary.

Moreover, when the varnish 13a is heated, the solvent etc. in the varnish 13 evaporate, and when this may intrude into the thermosiphon chamber 4, the base material exit part 4b immersed in the varnish 13, The substrate passage at the part 3) is as narrow as possible within the range through which the substrate 1 can pass, so that the interface area between the varnish storage region 3 'and the thermosiphon region 4', that is, the substrate exit portion 4b. It is good to keep the varnish surface area small.

For example, as shown in FIG. 6, the base material outlet part 4b immersed in the varnish 13, ie, the heating wall 32b, is comprised by the metal nozzle 34. As shown in FIG. The nozzle 34 has a flow hole 34a of a heat medium. Is formed, and is configured to heat the varnish beef 13a above the boiling point of the low-viscosity liquid 12. Moreover, it is preferable to form the heat insulation layer 35 in the outer surface of the nozzle 34 so that the varnish 13 around it may not be heated.

In this way, the evaporation of the solvent in the varnish 13 due to the heating of the varnishes 13a can be prevented as much as possible, and the vapor enters the thermosiphon chamber 4. It can prevent as much as possible.

In addition, condensation of the low-viscosity liquid vapor 12s on the liquid surface 13'a of the varnishes 13a can be prevented as much as possible. In addition, as shown in FIG. 6, the vapor ejection nozzle 36 which blows low viscosity liquid vapor 12s into the base-material outlet part 4b is shown. You can install it.

In this way, it interacts with the heating action by the circumferential wall 4c of the thermosiphon chamber 4 described above, and it is possible to promptly start the operation at the time of starting the device. Moreover, as shown in FIG. 7, the upper surface of the low-viscosity liquid storage tank 2 is closed by the lid 2c which holds the inlet 2d of the base material 1, and the cooling coil etc. are in the inlet 2d. It is also possible to arrange the leakage of the cooler 37 for preventing leakage of steam.

In the inlet port 2d, the low viscosity liquid vapor 12s is condensed and liquefied by the cooler 37. Therefore, dissipation of the low-viscosity liquid 12 can be reliably prevented, environmental pollution and loss of the low-viscous liquid can be prevented, and even if it is flammable, it can be used safely as the low-viscosity liquid 12. Such a configuration is also applicable to the varnish storage diagram 3.

8 shows a fourth embodiment of the present invention.

The varnish impregnation apparatus of this embodiment includes a low viscosity liquid storage tank 2 and a varnish storage tank 3, a thermosiphon chamber 4, a base material heating mechanism 5, a cooling mechanism 6, a guide mechanism 7, and a condensate recovery mechanism ( 8), varnish impregnation amount adjusting mechanism 9, steam flow mechanism 41, and the like.

The steam flow mechanism 41 provides the low viscosity liquid reservoir 48 and the low viscosity liquid heater 43 in the base material outlet 4b, and arranges the magnetically controlled heater 44 in the low viscosity liquid 12a. It is done by The low viscosity liquid storage part 42 is formed in the lower end part of the base-material exit part 4a, and the low viscosity liquid 12 in the low viscosity liquid storage tank 2 burns | fries by making the lead 42a the low viscosity liquid storage tank 2. Quantitative storage. The liquid level of the low-viscosity liquid storage part 42 coincides with the liquid level 12 'of the low-viscosity liquid storage tank 2 in spite of the evaporation of the low-viscosity liquid from the storage part 42.

The low-viscosity liquid heater 43 is composed of a jacket structure wall surrounding the low-viscosity liquid storage section 42. The low-viscosity liquid of the low-viscosity liquid storage section 42 is supplied by supplying and flowing a suitable heating medium therein. It is to evaporate (12).

The jacket wall in the low-viscosity liquid heater 43 is made of a heat insulating material except for the portion in contact with the low-viscosity liquid storage part 42 and the varnishes 13a, and the heat is applied to the varnish 13 around the varnishes 13a. It is designed not to be heated. In addition, the low-viscosity liquid heater 43 is constituted by a series of jacket structure walls communicating with the main wall 4c of the thermosiphon chamber 4. The self-regulating heater 44 is composed of a heat transfer coil for supplying and flowing a heating medium therein, and heat evaporates the low viscosity liquid 12 of the low viscosity liquid stream 12a.

This self-regulating heater 44 has a lower evaporation capacity than the low viscosity liquid heater 43, but has a low viscosity liquid heating surface 44a extending in the vertical direction in the low viscosity liquid stream 12a. The vapor pressure in the thermosiphon chamber 4 is configured to control the evaporation capacity. This function is similar to the low viscosity liquid heating mechanism 21 described above.

In this embodiment, the low-viscosity vapor 12s generated in the thermosiphon chamber 4, as shown by the broken line in FIG. 8, the amount of evaporation by the self-regulating heater 44 decreases as the vapor pressure increases. And in addition to each other, it flows further from the substrate outlet portion 4b toward the substrate heating portion 5a toward the substrate inlet portion 4a, and at least the substrate passes from the substrate heating portion 5a to the varnishes 13a. The area portion is reliably maintained in a low viscous liquid saturated steam atmosphere in which no air is present. Therefore, the varnish-impregnation property and voidless effect in the base material 1 are undoubtedly improved.

In the steam flow mechanism 41, as shown in FIG. 9, a cooler 45 such as a cooling coil may be provided on the substrate inlet 4a side instead of the heater 44 described above. The low viscous liquid vapor 12s generated in the thermosiphon chamber 4 is condensed by the cooler 45 and recovered to the low viscous liquid stream 12a, resulting in the flow of the low viscous liquid vapor 12s. Let's do it.

In this case, the weight 14 is not particularly necessary. Moreover, neither the heater 44 nor the cooler 45 mentioned above may be provided in the base material inlet part 4a side as shown in FIG.

As shown in FIG. 10, as shown in FIG. 7, the lid 2c and the cooler 37 are provided to prevent the dissipation of the low-viscosity vapor 12s. 11, the low viscosity liquid collection | recovery part 4b may be provided in the base material outlet part 4b, and it may be made to communicate 46a to the low viscosity liquid storage part 42. FIG. In this case, the cooler 45 is disposed in the low-viscosity liquid recovery part 46 to condense and recover the low-viscosity liquid vapor to the low-viscosity liquid recovery part 46.

12 shows a fifth embodiment.

This embodiment is basically the same as the fourth embodiment, but differs from each of the embodiments described above in the step of transferring the substrate inlet portion 4a from the low viscosity liquid reservoir 2 into the thermosiphon chamber 4. Although it becomes coarse with air, since the low viscosity liquid 12 is impregnated in the base material 1, air does not reintrude in the step before entering into the thermosiphon chamber 4.

Accordingly, no problem is caused by not enclosing the base material inlet portion 4a in the branch liquid storage region 2 '. In this case, as shown in FIG. 13, the apparatuses 2c and 37 which prevent the dissipation of the low-viscosity liquid vapor 12s in the low-viscosity liquid storage tank 2 can be provided. The effect by such an apparatus is further larger than the case where the base material inlet part 4a is liquid-sealed. In addition, as shown in FIG. 14, the condensate may be directly recovered from the substrate inlet 4a to the low-viscosity storage tank 2 without providing the low-viscosity liquid recovery section 46.

Claims (19)

The sheet-like base material made of a fibrous material is a low-viscosity liquid storage region 2 'in which a low-viscosity liquid 12 such as a solvent is stored, and a varnish storage region in which the storage region 2' and the varnish 13 are stored. Disposed between the thermosiphon region 4 'and the varnish storage region 3' which communicate with the varnish storage region 3 'in a liquid sealed state as the liquid surface 13' in order. And a step of heating the sheet-like base material (1) in the thermosiphon region (4 ') and evaporating the low-viscosity liquid (12) impregnated therein. The substrate 1 in the substrate passage region portion 32 'from the substrate heating portion 5a in the thermosiphon region 4' to the varnish storage region 3 '. A varnish impregnation method for heating or keeping above a condensation temperature of a low viscosity liquid vapor (12s). The varnish impregnation method according to claim 1, wherein the low-viscosity vapor (12s) generated in the heat sapon region (4 ') is condensed to recover the condensed low-viscosity (12). The low-viscosity liquid 12 according to claim 1, wherein the thermosiphon region 4 'is connected to the low-viscosity liquid storage region 2' in a liquid sealed state at the liquid surface 12 ', and the low-viscosity liquid 12 in the communicating portion 12a. ), And the varnish impregnation method in which the evaporation amount is controlled in accordance with the fluctuation of the liquid sealing surface at the communicating portion (12a). 2. The varnish impregnation method according to claim 1, wherein in the thermocypine region (4 '), the low-viscosity liquid vapor (12s) generated in the region (4') is caused to flow from the substrate outlet side toward the substrate inlet direction. The varnish impregnation method according to claim 1, wherein the communication portion between the thermosiphon region (4 ') and the varnish storage region (3') is heated and warmed to a temperature above the boiling point of the low viscosity liquid (12). Low viscous liquid storage tank 2 in which low viscous liquid 12 such as a solvent is stored, varnish storage tank 3 in which varnish 13 is stored, and liquid level 12 'or lower liquid level 12 in low viscous liquid storage tank 2 The thermosiphon chamber 4 having the substrate inlet portion 4a opened on the ') and the substrate outlet portion 4b opened on the liquid surface 13' of the varnish storage tank 3, and a fibrous material. The guide mechanism 7 which guides the sheet-shaped base material 1 to pass through the low viscosity liquid storage tank 2, the thermosiphon chamber 4, and the varnish storage tank 3 in order, and the base material in the thermosiphon chamber 4 The varnish impregnation apparatus provided with the base material heating mechanism 5 which heats (1) and evaporates the low viscosity liquid 12 impregnated in this. The condensate according to claim 7, wherein the cooling mechanism (6) for condensing the low-viscosity vapor (12s) in the thermosiphon chamber (4) and the low-viscosity liquid (12) condensed by the cooling mechanism (6) are recovered. Varnish impregnation device having a recovery mechanism (8). 8. The condensation flow of the low viscosity liquid vapor 12s in the substrate passage region portion 32 'from the substrate heating mechanism 5 to the opening end of the substrate outlet portion 4b. The varnish impregnation apparatus provided with the condensation prevention mechanism 31 which heats or keeps warm above. The low-viscosity liquid heating surface 21a which extends in the vertical direction to the low-viscosity liquid 12a in the substrate inlet portion 4a opened under the liquid surface 12 'of the low-viscosity liquid storage tank 2 further. The varnish impregnation apparatus provided with the low viscosity liquid heating mechanism 21 comprised so that the heat evaporation amount of the low viscosity liquid 12 may change according to the fluctuation | variation of the liquid surface 12'a of the low viscosity liquid flow 12a. The low-viscosity liquid storage part 42 and the low-viscosity liquid heater 42 are each provided with the low-viscosity liquid storage part 42 and the low-viscosity liquid heater 43 in the base material outlet part 4b. And a varnish impregnation device having a vapor flow mechanism (41) for flowing low viscosity liquid vapor (12s) generated in the thermosiphon chamber (4) toward the substrate inlet portion from the substrate outlet portion (4b). The varnish impregnation apparatus according to claim 11, wherein the low viscosity liquid storage tank (2) and the low viscosity liquid storage portion (42) are in communication with each other. 12. The low viscosity liquid recovery part (46) provided in the base fluid inlet part (4a) and communicated with the low viscosity liquid storage part (42) again, and this low viscosity liquid recovery part (46). Varnish impregnation device having a cooler (45) disposed. 8. The varnish impregnation apparatus according to claim 7, wherein the circumferential wall (4c) of the thermosiphon chamber (4) has a jacket structure, and the heating medium is supplied and flowed in the jacket. The heating apparatus 32b, 34, 34a, 43 which installs the boundary part with the varnish liquid surface 13'a more than the boiling point of the low-viscosity liquid 12 in the base material outlet part 4b. Varnish impregnation device. The varnish impregnation apparatus according to claim 15, wherein the cross-sectional area of the substrate passage at the substrate outlet portion (4b) is minimized within a range that allows passage of the substrate (1). The varnish impregnation apparatus according to claim 7, further comprising a varnish impregnation amount adjusting mechanism (9) for adjusting the varnish amount contained in the substrate (1) that has passed through the varnish storage tank (3). 8. The varnish impregnation device according to claim 7, further comprising a vapor ejection nozzle (36) for supplying low viscosity liquid vapor (12s) into the thermosiphon chamber (4 '). 8. The inlet port of the base material 1 formed in the lid 2c, while closing the upper surface portion of the low-viscosity liquid storage tank 2 with the lid 2c to which the base inlet 4a is attached. A varnish impregnation device (2d) provided with a coolant for preventing leakage of steam (37).

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